text: import { Vector3 } from './Vector3.js';
  import { _Math } from './Math.js';
  
  /**
   * @author bhouston / http://clara.io
   */
  
  var _startP = new Vector3();
  var _startEnd = new Vector3();
  
  function Line3( start, end ) {
  
  	this.start = ( start !== undefined ) ? start : new Vector3();
  	this.end = ( end !== undefined ) ? end : new Vector3();
  
  }
  
  Object.assign( Line3.prototype, {
  
  	set: function ( start, end ) {
  
  		this.start.copy( start );
  		this.end.copy( end );
  
  		return this;
  
  	},
  
  	clone: function () {
  
  		return new this.constructor().copy( this );
  
  	},
  
  	copy: function ( line ) {
  
  		this.start.copy( line.start );
  		this.end.copy( line.end );
  
  		return this;
  
  	},
  
  	getCenter: function ( target ) {
  
  		if ( target === undefined ) {
  
  			console.warn( 'THREE.Line3: .getCenter() target is now required' );
  			target = new Vector3();
  
  		}
  
  		return target.addVectors( this.start, this.end ).multiplyScalar( 0.5 );
  
  	},
  
  	delta: function ( target ) {
  
  		if ( target === undefined ) {
  
  			console.warn( 'THREE.Line3: .delta() target is now required' );
  			target = new Vector3();
  
  		}
  
  		return target.subVectors( this.end, this.start );
  
  	},
  
  	distanceSq: function () {
  
  		return this.start.distanceToSquared( this.end );
  
  	},
  
  	distance: function () {
  
  		return this.start.distanceTo( this.end );
  
  	},
  
  	at: function ( t, target ) {
  
  		if ( target === undefined ) {
  
  			console.warn( 'THREE.Line3: .at() target is now required' );
  			target = new Vector3();
  
  		}
  
  		return this.delta( target ).multiplyScalar( t ).add( this.start );
  
  	},
  
  	closestPointToPointParameter: function ( point, clampToLine ) {
  
  		_startP.subVectors( point, this.start );
  		_startEnd.subVectors( this.end, this.start );
  
  		var startEnd2 = _startEnd.dot( _startEnd );
  		var startEnd_startP = _startEnd.dot( _startP );
  
  		var t = startEnd_startP / startEnd2;
  
  		if ( clampToLine ) {
  
  			t = _Math.clamp( t, 0, 1 );
  
  		}
  
  		return t;
  
  	},
  
  	closestPointToPoint: function ( point, clampToLine, target ) {
  
  		var t = this.closestPointToPointParameter( point, clampToLine );
  
  		if ( target === undefined ) {
  
  			console.warn( 'THREE.Line3: .closestPointToPoint() target is now required' );
  			target = new Vector3();
  
  		}
  
  		return this.delta( target ).multiplyScalar( t ).add( this.start );
  
  	},
  
  	applyMatrix4: function ( matrix ) {
  
  		this.start.applyMatrix4( matrix );
  		this.end.applyMatrix4( matrix );
  
  		return this;
  
  	},
  
  	equals: function ( line ) {
  
  		return line.start.equals( this.start ) && line.end.equals( this.end );
  
  	}
  
  } );
  
  
  export { Line3 };
  